Positioning device for hydraulic operators



Jan. 29, 1935. KMBALL 1,989,235

POSITIONING DEVICE FOR HYDRAULIC OPERATORS Filed Mar ch 24, 1954INVENTOR.

Patented Jan. 29, 1935 PAr-ENT [omen POSITIONING DEVICE FOR-HYDRAULIC.

. OPERATORS,

Linwood Kimball, Danvers, assignor to Ruggles-Klingemann Mfg..C0.',Salem, Mass.

Application March 24, 1934, Serial No. #17320 5 Claims, (01. 192- 2),

My invention-relatesto a positioning device for hydraulic operators ofthe typedisclosed in the patent of-William J. Woods, Number-1,901,620 ofMarch-14, 1933, or for general applicationtosin'gle acting hydraulicoperated plungers in which the plungeris'biased to one of itsend,positions.- f

The object of my invention is to provide a self acting brake whichwill-prevent, the plunger from returning to its biased position onfailure of the m3 fluid pressure supply which operates the plunger andto provide magnetic means for releasing said brake. j 7

Another object is to provide dash pot means to insurea relatively slowreturn to the biased posi- 155 tion when the brake is released by themagnetic means.

For a more specific description of my invention, reference shouldbe'made to the accompanying drawing and to the above mention ofpatent.The drawing shows a vertical cross section of myinnti n.

Inthe drawing the casing (10) is provided with the cover (11) whichsupports the motor '.(12), whichdrives the impeller, (19)v byfme'ans ofthe shaft (20). The piston (21). slidesjwithin the sleeve (13), and hasan opening-thereinthrough which-the oil.tube, (17) extends. Supported bythe, piston.(2l) are the push rods (22) and. (23), having a, bridgingmember (24) supportingthe worksengaging eye (25).

The operationofthe device is asfollows: When the motor (12) isenergized,the impeller (19) will rotate. The impeller forces the oil in a radialdirection through the passageway (17') thus creating a pressuredifferential between opposite sides of the piston (21) to move itupwards in a vertical direction.

Without the application of my positioning device the motor onde-energization would cause the impeller to quickly come to a standstilland the pressure under piston (21) soon drop causing the piston torapidly return to its initial position.

In the application of the Woods operator which I have briefly described,it is sometimes found desirable to stop the motor without having thepiston (21) return to its initial biased,

position and to provide means whereby it can be positioned at anyposition between its limits of operation in either direction.

For the above reason I have devised effective positioning means which Iwill now describe.

To the work engaging eye (25) I have attached a closed dash pot cylinder(1) which is moveable up and down with the movement of piston (21).Within this cylinder is mounted a piston (2).

This piston (2) is-held stationary by means of piston rod (3) and itsconnection to stationary support (4). The cylinder (1) passes through atapered opening in; stationary support (4). jA

number of ball bearings(5) are provided in the :15

Clearance spacebetween the cylinder and "the tapered opening; These ballbearings are normally wedged into thesmall end of the tapered opening bymeans of spring (6). The arrange-, ment being such that the upwardmovement of 1 the cylinder (1) dislodges these ball bearings from theirclosely wedged position and allows a free upward movement of thecylinder (1'), but pro vides a check or brake against any returnmovement when the motor (12) isde-energized;

To release this brake and, allow for the return m'ovementjasolenoid (31)is provided,v having plunger (7) operating arm (8) pivoted at position(9). This arm is yoked aroundcylinder (1 and engages a sleeve (26) atpoint '(27). When Q this; solenoid (3,1) is energized theplungerfl) isattracted raising, arm (8) andforcing sleeve (26) upwardpermitting thesleeve to engage the under side ofrthe ball bearings and dislodge themfrom their closely wedged position,,thereby re-, 25 leasingthe cylinder(1). v

Suitable current forthe operation of the solenoid and motoris suppliedfrom main line L1 and L2; 'afltwo way switch .(28) is provided. whichcontrolsthe operationof the solenoidand the motor 0 to position thehydraulic operator.

, The operation is as: follows; Assuming that switch (28) is thrown tomake contact at (29), then the current flows from line L1 to the motorand back through switch (28) to line L2 and the hydraulic operatorslowly moved upward against the dash pot action of piston (2) incylinder (1) Assuming the switch is thrown to natural in the positionshown at the completion of the upward stroke or at some intermediateposition in the upward movement, then the motor (12) is stopped, and asthe cylinder (1) settles downward the ball bearings are forced into thesmall end of the taper and lock the operator in any position which itmay occupy against further downward movement.

Now, assuming it is required to return the operator to its initial orbiased position, or to some intermediate lower position, then the switch(28) is thrown to make contact at (30) and current flows from line L1 tothe solenoid (31) and back through switch (28) to line L2, energizingthe solenoid and releasing the brake and allowing the operator to slowlyreturn to its initial or biased position or to some intermediate lower 2position, depending on the operation of switch (28). The work engagingeye operates the work lever (32) which is pivoted on stationary supportframe (4) and point (33). To the opposite end of this lever (32) atpoint (34) may be attached to whatever device it is required to operate,such as valve, damper, rheostat or other like device. The return strokeof piston (21) and other moving parts to their biased position iseffected by means of spring (35) plus the weight of the moving parts.

It will now be seen that I have devised a novel positioning device forhydraulic" operators, or similar pressure actuated operatives.Modifications may be made by persons skilled in the art withoutdeparting from the spirit of my invention to be included within thescope of the invention,

as defined in the appended claims.

I claim: I

1. Ihe combination with a hydraulic operator having a cylinder with apiston therein, said piston being operable between two positions andbiased to one of said positions, fluid pressure actuating means foroperating said piston to the other position, ofa device for positioningsaid operator at intermediate positions comprising an oil dash potoperatively connected with said operator and adapted to effect a slowuniform operation of said operatorin either of two directions, of aself-acting, one way brake cooperating with a movable part of said dashpot and adapted to hold said operator at any intermediate position onfailure of the fluid pressure actuating means, and electric remotecontrol means for alternately operating the fluid pressure actuatingmeans and for. releasing said brake.

r 2. The combination with a hydraulic operator comprising a cylinderhaving a piston therein, said piston being operable between two endpositions and biased to one of said end positions, fluid pressureactuating means for operating said piston ,toithe other end position, ina positioning] device for said operator comprising an oil dash potadapted to effect a slow uniform motion of said operator in eitherdirection, of a selfacting, one way brake cooperating with a movablepart of said dash pot and adapted to hold said'operator at anyintermediate position between the fluid pressure operated position andits biased position, and remote control means for alternately operatingthe fluid pressure actuating means and for releasing said brake.

3. In a positioning device for hydraulic operators comprising incombination a cylinder having a piston therein, said piston beingmovable between two positions, fluid pressure means to operate saidpiston to the other position, an oil dash pot operatively connected withsaid piston comprising a closed cylinder having a loosely fitted pistontherein, a piston rod extending through a stufiing box at one endof saidcylinder and connected with a stationary support, a stationary guideblock for said dash pot cylinder having a conical interior bore andadapted to receive wedge brake members for preventing operation in thedirection of the biased position, and electric remote control means foroperating the fluid pressure means and for releasing said brake. 4. Thecombination with a hydraulic operator having a cylinder with a pistontherein, said piston being operable between two positions and biased toone of said positions, fluid pressure actuating means for operating saidpiston to the other position, of a device for positioning said piston atintermediate positions comprising an-oil dash pot operatively connectedwith said piston and adapted to effect a slow uniform motion of saidpiston in either direction, said dash pot comprising a cylinder having aloosely fitted piston therein constituting stationary and movableelements requiring in its operation displacement .of fluid from one sideof said piston to the other, a stationary guide block having a conicalinterior bore adapted to receive the movable part of said dash pot andto support wedge brake members for preventing operation in the directionof the biased position, and electric remote control means foralternately operating the fluid pressure actuating means and forreleasing said brake.

5. The combination with a hydraulicv operator having a reciprocatingmovable part operated in one direction by fluid pressure and in theopposite direction by spring tension, a positioning device for saidmovable part comprising a closed cylinder operably connected with saidmovable part, a piston in said cylinder, a piston rod extending througha stufling box at one end of said cylinder and connected with astationary support, a one-way, self acting wedge brake surrounding saidcylinder and preventing the operation of said movable part in onedirection by the spring tension on failure of the fluid pressure, andremote control means for alternately effecting the operation in onedirection by fluid pressure and in the opposite direction by releasingsaid brake. LINWOOD, KIMBALL.

